Abstract
Inducible nitric oxide synthase (iNOS) and TGF-beta were localized by immunocytochemistry in skin lesions from patients across the leprosy spectrum, and from patients undergoing reversal reaction. iNOS expression was highest at the tuberculoid pole of the spectrum, and increased during reversal reaction. TGF-beta was observed throughout the leprosy spectrum, but was highest at the lepromatous pole. Levels of TGF-beta decreased during reversal reaction. Reduced levels of TGF-beta may contribute to unregulated inflammatory responses during reactional episodes.